Murine Models of Salmonella Infection

Abstract

The pathogen Salmonella enterica encompasses a range of bacterial serovars that cause intestinal inflammation and systemic infections in humans. Mice are a widely used infection model due to their relative simplicity and versatility. Here, we provide standardized protocols for culturing the prolific zoonotic pathogen S. enterica serovar Typhimurium for intragastric inoculation of mice to model colitis or systemic dissemination, along with techniques for direct extraintestinal infection. Furthermore, we present procedures for quantifying pathogen burden and for characterizing the immune response by analyzing tissue pathology, inflammatory markers, and immune cells from intestinal tissues. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Murine colitis model utilizing oral streptomycin pretreatment and oral S. Typhimurium administration Basic Protocol 2: Intraperitoneal injection of S. Typhimurium for modeling extraintestinal infection Support Protocol 1: Preparation of S. Typhimurium inoculum Support Protocol 2: Preparation of mixed S. Typhimurium inoculum for competitive infection Basic Protocol 3: Assessment of S. Typhimurium burden Support Protocol 3: Preservation and pathological assessment of S. Typhimurium–infected tissues Support Protocol 4: Measurement of inflammatory marker expression in intestinal tissues by qPCR Support Protocol 5: Preparation of intestinal content for inflammatory marker quantification by ELISA Support Protocol 6: Immune cell isolation from Salmonella‐infected intestinal tissues

Intestinal organoids to model Salmonella infection and its impact on progenitors

“…During the acute phase of infection, these animals develop overt signs of illness (including hunched posture, reduced movement, loss of body weight) typically appearing between 4 and 6 days post oral infection, with mortality occuring within the subsequent days. However, diarrhea does not develop 13 – 15 . To determine which intestinal segment is preferentially targeted by S. Typhimurium in mice, we determined the level of S. Typhimurium colonization in ileum, caecum, and colon of infected C57BL/6 mice at 4 days post-infection (p.i.).…”